Your father's mentality apparently is one in which sex is a mechanical arrangement of body parts. How sad.
When the question is restated as, "How do you and your partner make love?" the question is exposed as both trivial and rude. Trivial, because every loving couple does whatever pleasures both of them, with whatever combination of hands, mouths, other body parts, furniture, and toys appeal to them. And rude, because how would he like being asked what he does with his wife in private moments?
I'm wired cis, but I still have enough imagination to feel confident that any two (or more) people who sincerely wish to please each other will find many happy ways to do so.